A relatively new subculture (late 90's-present). A hipster can generally be identified as a skinny, efeminate looking male or a unkemp, annoyed looking female in their 20's wearing tight jeans and thrift store/vintage clothing and accesories.
The hipster is a subculture without a cause. They have no ideals or values except trying shunn the mainstream and appear as unconventianal as possible by advocating the independent. They can be seen: riding bikes, smoking expensive cigarretes, drinking independent coffee and cheap alchahol, and eating organic and vegan food. They will say they do such things so as to not conform to mainstream/consumer society, but really their only motive is to appear interesting and different. Theyr'e also pretentious as hell and have egos the size of Africa despite the fact that nobody really cares about them or their interests. They especially enjoy talking about themselves but will lose interest if the conversation moves to other subjects. They will not give up an argument but if confronted with violence they will quikly coil into the fetal position. Oh, and many male hipsters are closeted homosexuals.
Overall, hipsters are the embodiment of apathy, irony, and hypocrisy because by not conforming, theyr'e conforming.
The origin of the modern hipster is simple: Skinny, uncomfortable, nerdy guys in high school with small genetalia back in the late 90's couldn't find their identity and so decided to "not conform" by creating a sorry clusterfuck of a human being with oversized glasses and tight pants. The girls just did it to tag along and appear more interesting and inflate their egos.
The worst subculture out there in my opinion.
The CA bay area seems to be most heavily populated with hipsters, but you can find them at your local independant coffee shop.
hipster: I just rode my bike downtown while smoking a pack of cloves, then spent the day shopping at goodwill and loitering.
Me: Go fuck a duck.